The use of gas stoves for cooking is widespread. Although gas is much more convenient than other fuels, such as coal, gas is toxic and is hazardous to persons breathing the gas. The gas flame of a burner can be blown out by the wind and cause unburned gas to leak from a burner. Such unburned gas can easily cause explosion, and threaten life and property. Gas is also used as fuel for water heaters which are often installed outside a room or house. Unburned gas from a gas water heater also poses the above risks.
A further problem with typical gas stoves arises because they are operated manually. When foods are cooked over a gas burner, for example, the users often wander away and forget about the food. Boiling liquid may overflow and drown the burner flame, or food may dehydrate and ruin the cooking utensil, or even cause a fire.
All these problems cause financial and property loss in minor cases, or threaten life and property in major cases.